Problem: Is "The toaster Frank had sold him didn't work." true if "Frank was upset with Tom because the toaster he had sold him didn't work."?
Answer: no

Problem: Is "The shelf was too tall." true if "I couldn't put the pot on the shelf because it was too tall."?
Answer: no

Problem: Is "Mark should have been more truthful." true if "Mark told Pete many lies about himself, which Pete included in his book. He should have been more truthful."?
Answer: yes

Problem: Is "Even one thread uncut will leave the scissors too small." true if "It is not easy to space buttonholes exactly the same distance apart, and it is very difficult to cut them precisely the right size. The tiniest slip of the scissors will make the hole too large, and even one thread uncut will leave it too small."?
Answer:
no